Apparently the feeling of optimism caused by the combination of lighter evenings, the prospect of holidays and memories of childhood summers is at its peak on June 20.
According to the research this has been worked out using the equation O + (N xS) + Cpm/T + He.
O stands for being outdoors and outdoor activity, N is connection with nature, which is in full bloom now, S is socialisation with neighbours and friends, Cpm stands for childhood positive memories, T is the mean temperature which is now usually warm, and He is holiday expected.
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